Digital roots

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To find the digital root of a number, you add the digits repeatedly until you reach a single digit number. For example, the digital root of 169 is 7 because 1 6 9 16, and 1 6 7 The digital roots of the first 9 square numbers are given in the table below:




(a) Complete the table of digital roots of the next nine square numbers.




Comments

  1. Anonymous2 August 2021 at 18:19

    1 + 0 + 0 = 1

    1 + 2 + 1 = 4

    1 + 4 + 4 = 9

    1 + 9 + 6 = 1 + 6 = 7

    2 + 2 + 5 = 9

    2 + 5 + 6 = 1 + 3 = 4

    2 + 8 + 9 = 1 + 9 = 1 + 0 = 1

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